Design rule says that the 5 times of the busbar thickness is the minimum overlap requirement. The BlokSeT switchboard uses 5 mm thick busbars. Hence, 25 mm overlap is used in all busbar joints. Please refer to the below picture and attached Technical Report for more information.



However, IEC 61439 does not suggest that what should be overlap dimension. Temperature Rise test is the ultimate proof of joint resistance. All the joints are validated by Temperature Rise Test as per IEC 61439-1&2 in BlokSeT.

Released for: Schneider Electric New Zealand